1. Field of the Invention
The present invention relates to functionalizable and crosslinkable polyurethanes, the process of functionalizing, the process of crosslinking and the functionalized and crosslinked products derived from the functionalizable and crosslinkable polyurethanes. In particular, the present invention is concerned with crosslinked and functionalized polyether polyurethanes, the products thereof and their uses in industrial products, cosmetics and medical devices.
2. Description of Related Art
Polyurethanes that contain carboxyl groups in the backbone are known in the art. U.S. Pat. No. 4,743,673 describes the preparation of hydrophilic carboxylic acid containing polyurethanes by using diesters of dihydroxyl carboxylic acids such as the butyl ester of tartaric acid, to form polyurethane intermediates. The polyurethane intermediates are saponified and neutralized to form free carboxyl groups. This patent describes that the carboxyl groups introduce reactive sites for attaching side groups and for curing procedures. The carboxyl groups also provide sites for light or loose crosslinking curing with ammonium dichromate which can oxidize or complex with the acid group. This patent has the shortcoming that only ammonium dichromate is used and it is toxic and such products are not useful in cosmetics and medical devices.
U.S. Pat. No. 3,412,054 describes a water dilutable polymer for use as surface coatings and inks. The polyurethanes are prepared by reacting an amine or ammonia with a urethane polymer containing free carboxyl groups to form a polymer including a quaternary ammonium salt. This patent describes those polymers containing alkanoic acids that form quaternary ammonium groups in the presence of an amine but do not form the amide. Accordingly, the ammonium salt is formed and it can be functionalized but the quarternary group ionizes readily in water and is not stable.
U.S. Pat. No. 5,254,662 describes that polyurethanes prepared from the reaction of an organic diisocyanate with polycarbonate glycol can be chain extended with a diol, diamine or a mixture of diamine and alkanolamine. This patent discloses that the polyurethane formed is biostable and can be used in implantable pacemakers, vascular grafts, mammary prostheses and as other products which are intended to be placed in the body.
It is desirable to form a functionalized and crosslinked polymer using a polyether and polycarbonate polyurethane which can be used in industrial products, cosmetics and medical devices.